RIP Philo

### So my placement exam is tonight

I've hardly had any time to brush up on my algebra.

Anybody know a good place for an algebra refresher?  Especially factoring polynomials and shit?
muppet
March 29th, 2007 7:38am
... here? We have quite a few math wizzes.

/me is no help at all.
~~~x
March 29th, 2007 7:41am
Read over one of those plastic guide-to-algebra they have at the bookstore?

Good luck!

March 29th, 2007 8:52am
I'm reading the Wikipedia entry on polynomials right now.
muppet
March 29th, 2007 9:31am
"A polynomial of degree zero is called a constant, of degree one is called linear, of degree two is called quadratic, of degree three is called cubic. Less commonly used, degree four is called quartic and degree five quintic."

I was never taught this naming convention in school, at least not in this way, so until I just read this I had no idea WHY equations were called linear, quadratic, etc...

muppet
March 29th, 2007 9:33am
S.A.T. study guides
Walter Sobchak
March 29th, 2007 10:22am
and a degree sevn (if you are unlucky enough to meet one) is called a "septic".
\$--
March 29th, 2007 12:04pm
good luck mupp
Kenny
March 29th, 2007 12:14pm
This is the GRE? I think I have some GRE test prep material. Hit me up if you want me to fileshare.
~~~x
March 29th, 2007 12:31pm
Run, don't walk, to this site.  Best site EVAR! IMHO.

http://www.themathpage.com/Index.html
sharkfish
March 29th, 2007 12:32pm
Thanks shark.

I think I'm pretty boned anyway.  I didn't find time to study until last night, and that was not enough time.

Mark - It's the 'accuplacer', so I'm not sure what the fuck that is except that apparently it's a standard of some kind.
muppet
March 29th, 2007 12:33pm
http://www.collegeboard.com/highered/apr/accu/accu.html

Sounds like it's there to figure out if you can skip the 101 level stuff or if you need remedial instruction before you get to the 101 level stuff.
~~~x
March 29th, 2007 12:39pm
Oh, and it's accu and placer.
~~~x
March 29th, 2007 12:39pm
Well at the very least I should be able to test out of the remedial stuff.

I still can't factor polynomials to save my ass because it's not (to my mind) something you can easily derive mathematically.  You just sort of have to memorize the patterns.  Rote memorization is my worst enemy.
muppet
March 29th, 2007 12:41pm
Isn't that where you go like:

192 divisible by:

86
64
(half of 86, half of 64 etc)

And then plug in those numbers. I'm vague on the specifics, but there was a method.
~~~x
March 29th, 2007 12:54pm
No, it's like where you take:

a^2 + 2ab - 4

and factor it down to:

(a-2)^2
muppet
March 29th, 2007 12:55pm
Yeah, there is a method for that... I think I may have sold off my algebra text or I would have looked it up.
~~~x
March 29th, 2007 12:58pm
Do they let you use calculators? My Casio will do that sort of factoring for you. ;-)
~~~x
March 29th, 2007 12:59pm
No calculators.
muppet
March 29th, 2007 12:59pm
Anyway, don't you just go "What are the factors of -4? +2 and -2. So it must be (a+2)(a-2).

And if it was 16 you'd go "What are the factors of 16? 16*1, 8*2, 4*4." and plug them in?

Things get weird when you're up in the high exponent range where you can figure it out using n!-(n-x)!/n! or something, but for low exponents like 2 it's straightforward. When you get to cube root there's a similar method that involves setting up a table & subtracting the results to get possible square roots & there's a quick test to see if it's a possible solution by some easy math & comparing it to the remainder.
~~~x
March 29th, 2007 1:04pm
And in 8th grade I could totally rock it, Mark, but it's been way too long and those parts of my brain are dusty.

What annoys me is that I'll miss this stuff on the placer, and be forced to endure at least a full semester of instruction when it'll only take 2 or 3 classes for it all to click again.
muppet
March 29th, 2007 1:49pm
go find the quadratic formula.  then you have one formula to memorize and not all these patterns.
the great purple
March 29th, 2007 2:09pm
Yeah, memorize the solution for quadratics and you can use that until you get used to the patterns.

ax^2+bx+c=0

has two solutions:

x= [-b +- sqrt(b^2-4ac) ] / 2a

call those two values R1 and R2 and you factor the quadratic as

(x-R1)(x-R2)
Ward
March 29th, 2007 2:24pm
"I still can't factor polynomials"

I took Math to 2nd-level Calculus plus some Linear Algebra and Discrete stuff but I don't remember how to factor polynomials.  It might come back to me but it seems unlikely -- a lot of that calculus and other material didn't stick around much either.